textproduct: Albany

WHAT HAS CHANGED

Increased temperatures and lowered dew points this afternoon compared to the previous forecast. Also lowered temperatures Tuesday for northern areas with a warm front expected to become hung up across our region. Finally, increased chances for showers Thursday, but wintry precip now looks less likely outside of the high terrain areas Thursday/Friday.

KEY MESSAGES

1) Tranquil but breezy weather expected today.

2) A storm system will result in periods of rain and possible thunderstorms from Monday night through Wednesday. There is a low to medium potential for minor flooding to occur across the Adirondacks, although forecast confidence continues to remain low at this time.

3). Another storm system is expected to bring additional precipitation to the region Thursday into next weekend. Outside of the mountains, precipitation now looks to fall mainly as rain.

DISCUSSION

KEY MESSAGE 1... As of 2:25 AM EDT...Our region remains under zonal flow aloft with just a few mid and high clouds around associated with a weak, moisture-starved upper impulse. Where skies are clear and winds have decoupled, temperatures are in the upper 20s to low 30s, while the Hudson Valley from the Capital District continues to see light winds and more scattered clouds that are keeping temperatures in the mid to even upper 40s at this time.

While temperatures will be quite variable through shortly after sunrise, all areas should see temperatures warm fairly quickly this morning under partly cloud skies. Clouds increase by this afternoon, but not before temperatures climb well into the 60s for many valley locations thanks to deep pre-greenup BL mixing. Given deeply mixed profile, we also continued to increase wind gusts to 20-30 kt this afternoon, which is quite a bit higher than the NBM. Mixing down of mid-level dry air will also help offset moist advection this afternoon, so we dropped dew points a few to several degrees from the NBM as well. We could therefore see RH values drop to 35-40% this afternoon across the Hudson Valley and the lower elevations of western New England. While these RH values will be higher than yesterday, we have issued an SPS for an elevated risk of fire spread for western MA in coordination with MA state partners and WFO BOX.

KEY MESSAGE 2...Tonight, a strengthening LLJ with a Gulf moisture connection moves over the region, helping to increase low to mid-level warm advection. Isentropic lift along with some FGEN along the front and convergence at the nose of the LLJ will lead to scattered showers developing tonight as the warm front lifts north across the region.

Coverage of showers increases as the night goes on with steadier rain expected, especially for northern areas, by Tuesday morning. A wave of low pressure tracking along the warm front will lead to continued periods of rain Tuesday, especially for northern areas which will be closer to the front and the better forcing. Our southern zones will likely be drier, but a few showers can't be ruled out. The warm front will likely get hung up across our northern areas Tuesday, and so in coordination with WFO BTV we lowered temperatures Tuesday several degrees from the NBM in the typical areas against the east-facing slopes of the ADKs and southern Greens and in the upper Hudson Valley. For southern areas, temperatures still look quite warm, with low to mid 70s for the Mid Hudson Valley and southern Litchfield County.

A second, stronger wave of low pressure will track along the warm front Tuesday night. By this time, PWATs will have increased to around 1.3" across northern areas, which is 3-4 standard deviations above normal per the latest NAEFS. There will also be good moisture convergence and lift near the front, so Tuesday evening and night is the best chance for some periods of moderate to locally heavy rain across the ADKs. This second wave of low pressure will help push the front back south as a cold front late Tuesday night and Wednesday, which will lead to increasing shower chances across the rest of the region.

There will be pockets of elevated instability around Tuesday afternoon and night near and north of the warm front. While there may be some surface-based instability across our southwestern areas, there also looks to be more of a cap here and low-level forcing to overcome the cap in the warm sector is relatively weak. SPC has placed western portions of our area in a marginal risk for severe weather Tuesday, but this seems to account for a worst-case scenario, as lack of surface based instability/lack of forcing to overcome any cap suggests that the chances for severe weather are very low in our CWA. That said, some non-severe thunder will be possible Tuesday and Tuesday night with showalter values <0 across much of the region. A few more rumbles of thunder will be possible for southern areas Wednesday afternoon as the cold front arrives as well. Low confidence on temperatures Wednesday for northern areas, as this will heavily depend on how early in the day the cold front drops south. For our southernmost areas, temperatures likely rise well into the 70s though ahead of the cold front.

Showers taper off Wednesday evening. By this point, QPF amounts look to range from a quarter to half inch for southern areas to as high as 2 inches across the ADKs. With some snow still on the ground in the ADKs, the combination of rain and snowmelt will lead to enough runoff for river rises. For the ADKs and rivers draining the ADKs, there remains a low to medium chance for minor flooding, particularly on the West Canada Creek and Schroon River. However, per conversations with the NERFC, ensemble forecasts for rivers are likely overdone on the flood potential due to the models overestimating the amount of available snow to melt out. Outside of the aforementioned areas, within-bank river rises are expected, but probability for flooding is quite low.

KEY MESSAGE 3...Some larger changes to the forecast for the end of the week vs previous forecasts: Whereas the cold front previously looked to settle well south of our region Wednesday night, it now looks to only drop to around the I-84 corridor thanks to a more amplified west Atlantic upper ridge. This will not only reduce the amount of cool air filtering into our region behind the front, but will also shift the track of the next storm further west. This boundary will likely lift back north as a warm front Thursday, bringing with it additional chances for some showers. There is still somewhat of a cold air damming signal across northern areas where a brief wintry mix may be possible Thursday, but for the rest of the region precip now looks to be mainly plain rain. The sfc low tracks to our north Friday, putting our region in the warm sector with chances for scattered showers late in the day or at night with the system's cold frontal passage. Another sfc low tracking to our W/NW over the weekend could bring additional showers ahead of its cold front as well, so the end of the week into next weekend looks to remain on the wetter side.

AVIATION /12Z MONDAY THROUGH FRIDAY/

VFR conditions continue through the 00z timeframe for all TAF sites. After 31/00z, MVFR/VFR conditions could fluctuate between 00z and 03z with ceilings gradually lowering between 03z and 06z to MVFR. After 31/06z, ceilings and visibilities could fluctuate between MVFR/IFR conditions due to increasing chances of rain showers through the end of the TAF period. Rain shower activity after 06z has been introduced to all TAF sites with PROB30 groups with increasing confidence for periods of IFR conditions.

Low level wind shear continues at KPOU and KPSF through this morning as winds around two kft continue to range between 30 and 40 knots from the southwest. Otherwise, light and variable winds continue this morning except for at KALB. Southeasterly winds between 5 and 10 knots continue at KALB. Winds increase this afternoon between 15 and 25 knots. Winds decrease after 22-23z to less than 15 knots and continue to decrease into the overnight hours.

Outlook...

Tuesday Night: High Operational Impact. Definite RA...TSRA. Wednesday: Moderate Operational Impact. Breezy. Chance of SHRA. Wednesday Night: Moderate Operational Impact. Chance of SHRA. Thursday: High Operational Impact. Likely SHRA. Thursday Night: Moderate Operational Impact. Chance of RA. Friday: High Operational Impact. Likely RA...TSRA. Friday Night: Moderate Operational Impact. Chance of RA. Saturday: Moderate Operational Impact. Chance of RA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.